U.S. patent number 6,415,391 [Application Number 08/532,886] was granted by the patent office on 2002-07-02 for control method and system for resetting backup data.
This patent grant is currently assigned to NEC Corporation. Invention is credited to Yoshihiro Naka.
United States Patent |
6,415,391 |
Naka |
July 2, 2002 |
**Please see images for:
( Certificate of Correction ) ** |
Control method and system for resetting backup data
Abstract
A backup control system comprises a control package, a file
package including a battery monitor and a flip-flop circuit, and a
back board having a return wire which provides
connection/disconnection of the monitor terminal of the monitor.
The monitor checks a voltage of the monitor terminal at all times
and outputs a reset signal to the flip-flop circuit when the
voltage of the monitor terminal becomes lower than a reference
voltage. The return wire connects the monitor terminal to the power
line when the file package is connected to the connection board,
and disconnects the monitor terminal from the power line when the
file package is removed from the connection board. The flip-flop
circuit stores one of a set state and a reset state, and changes in
state from the set state to the reset state when the reset signal
is received from the monitor.
Inventors: |
Naka; Yoshihiro (Tokyo,
JP) |
Assignee: |
NEC Corporation (Tokyo,
JP)
|
Family
ID: |
16864213 |
Appl.
No.: |
08/532,886 |
Filed: |
September 22, 1995 |
Foreign Application Priority Data
|
|
|
|
|
Sep 22, 1994 [JP] |
|
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6-227651 |
|
Current U.S.
Class: |
714/21; 714/22;
714/24; 714/E11.133; 714/E11.138 |
Current CPC
Class: |
G06F
11/1417 (20130101); G06F 11/1441 (20130101) |
Current International
Class: |
G05B
23/02 (20060101); G06F 11/00 (20060101); G06F
1/30 (20060101); G06F 12/16 (20060101); G06F
011/00 () |
Field of
Search: |
;714/23,22,15,21,29 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Baderman; Scott
Attorney, Agent or Firm: Sughrue Mion, PLLC
Claims
What is claimed is:
1. A system comprising:
a connection board;
a plurality of circuit packages being detachably connected to said
connection board, each of the plurality of circuit packages using
start-up setting data for start-up operation;
a first package detachably connected to the connection board and
comprising:
a backup memory for storing the start-up setting data,
a disconnection detector for detecting disconnection of the first
package from the connection board to produce a disconnection
signal, and
a state memory for storing one of a first state and a second state
such that the second state is normally stored and is changed to the
first state when the disconnection signal is produced; and
a second package for controlling the plurality of circuit packages
and the first package through the connection board, the second
package being detachably connected to the connection board and
comprising a controller for determining whether the start-up
setting data stored in the backup memory is valid by checking which
of the first state and the second state is stored in the state
memory of the first package.
2. The system according to claim 1, further comprising:
the first package having a battery for supplying power to a power
line; and
the disconnection detector comprising:
a monitor monitoring a voltage of a monitor input terminal, the
monitor generating the disconnection signal when the voltage of the
monitor input terminal becomes lower than a predetermined reference
voltage, and
a connector connecting the monitor input terminal of the monitor to
the power line when the first package is connected to the
connection board, and disconnecting the monitor input terminal from
the power line when the first package is removed from the
connection board.
3. The system according to claim 1, wherein:
the first package further comprises a battery for supplying power
to a power line; and
the disconnection detector comprises:
a monitor monitoring a voltage of a monitor input terminal, the
monitor generating the disconnection signal when the voltage of the
monitor input terminal becomes lower than a predetermined reference
voltages and
a first connector having a first plurality of conductors for
electrically connecting the first package to the connection board,
the first plurality of conductors including a first conductor
connected to the power line and a second conductor connected to the
monitor input terminal of the monitor; and
the connection board comprises a second connector having a second
plurality of conductors and detachably connecting to the first
connector, the second plurality of conductors of the second
connector corresponding to the first plurality of conductors of the
first connector, the respective second plurality of conductors
including a third conductor corresponding to the first conductor
and a fourth conductor corresponding to the second conductors the
third and the fourth conductors being connected to each other.
4. The system according to claim 2, wherein the monitor monitors a
voltage of the battery through the power line and the connector
when the first package is connected to the connection board.
5. The system according to claim 3, wherein the monitor monitors a
voltage of the battery through the power line and the first and
second connectors when the first package is connected to the
connection board.
6. The system according to claim 3, wherein the monitor generates
the disconnection signal when the first package is removed from the
connection board.
7. The system according to claim 2, wherein the predetermined
reference voltage is higher than a minimum voltage that assures
holding of data stored in the backup memory and the state
memory.
8. The system according to claim 3, wherein the predetermined
reference voltage is higher than a minimum voltage that assures
holding of data stored in the backup memory and the state
memory.
9. The system according to claim 1, wherein the state memory is a
flip-flop circuit having a set terminal, a reset terminal and an
output terminal, the reset terminal receiving the disconnection
signal from the disconnection detector, and the output terminal
indicating one of the first state and the second state.
10. A method for backing up setting data in a control system, the
control system comprising
a connection board;
a plurality of circuit packages detachably connected to said
connection board, each of the plurality of circuit packages using
start-up setting data for start-up operation;
a first package detachably connected to the connection board, the
first package including a backup memory for storing the start-up
setting data; and
a second package for controlling the plurality of circuit packages
and the first package through the connection board, the second
package being detachably connected to the connection board;
the method comprising the steps of:
a) detecting disconnection of the first package from the connection
board to produce a disconnection signal;
b) storing one of a first state and a second state such that the
second state is normally stored and is changed to the first state
when the disconnection signal is produced; and
c) determining whether the start-up setting data stored in the
backup memory is valid depending on which of the first state and
the second state is stored.
11. The method according to claim 10, wherein:
the first package includes a battery for supplying power to a power
line; and
the step a) comprises:
monitoring a voltage of a monitor terminal such that the
disconnection signal is produced when the voltage of the monitor
terminal becomes lower than a predetermined reference voltage:
connecting the monitor terminal to the power line when the first
package is connected to the connection board; and
disconnecting the monitor terminal from the power line when the
first package is removed from the connection board.
12. The method according to claim 11, wherein said step a) further
comprises monitoring a voltage of the battery through said power
line when said first package is connected to the connection
board.
13. The method according to claim 10, wherein the step a) comprises
producing the disconnection signal when the first package is
removed from the connection board.
14. The method according to claim 11, wherein the step a) comprises
producing the disconnection signal when a voltage of the battery
becomes lower than the predetermined reference voltage.
15. The method according to claim 11, further comprising a step of
setting the predetermined reference voltage higher than a minimum
voltage that assures holding of data stored in the first
package.
16. A backup memory package detachably connected to a control
system through a connection board, the control system controlling a
plurality of circuit packages and the backup memory package through
the connection board, each of the plurality of circuit packages
using start-up setting data for start-up operation, the backup
memory package comprising:
a backup memory for storing the start-up setting data;
a disconnection detector for detecting disconnection of the backup
memory package from the connection board to produce a disconnection
signal; and
a state memory for storing one of a first state and a second state
such that the second state is normally stored and is changed to the
first state when the disconnection signal is produced.
17. The backup memory package according to claim 34, further
comprising:
a battery for supplying power to a power line, and the
disconnection detector comprising:
a monitor for monitoring a voltage of a monitor input terminal the
monitor generating the disconnection signal when the voltage of the
monitor input terminal becomes lower than a predetermined reference
voltage; and
a connector for connecting the monitor input terminal of the
monitor to the power line when the first package is connected to
the connection board, and for disconnecting the monitor input
terminal from the power line when the first package is removed from
the connection board.
18. The backup memory package according to claim 17, wherein, when
the first package is connected to the connection board, the monitor
monitors a voltage of the battery through the power line and the
connector.
19. The backup memory package according to claim 17, wherein the
predetermined reference voltage is higher than a minimum voltage
that assures holding of data stored in the backup memory and the
state memory.
20. The backup memory package according to claim 16, wherein:
the state memory is a flip-flop circuit having a set terminal, a
reset terminal, and an output terminal;
the reset terminal receives the disconnection signal from the
disconnection detector; and
the output terminal indicates one of the first state and the second
state.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a system for backing up setting
data of a plurality of circuit packages and, more specifically, to
a backup method and system in a control system having a detachable
backup memory.
2. Description of the Related Art
In general, a transmission apparatus in a switching system has a
number of circuit packages (built-in circuit boards) which are
detachably mounted on the backboard of the apparatus frame. This
type of transmission apparatus further has a file package including
a backup memory which stores start-up setting data such as a line
connections state and a soft strap setting state of the
transmission apparatus. When a communication service of the
switching system is stopped due to, for instance, power shutoff,
the communication service can be restored in a short time by using
the start-up setting data stored in the backup memory.
FIG. 1 is a schematic block diagram showing a conventional control
system having such a file package. A control package 10, a host
supervisory/controlling apparatus (i.e., a central control
apparatus) 20, a plurality of circuit packages 30 to be set, and a
file package 40 are connected to each other via a backboard. Each
of the circuit packages 10, 30 and 40 are detachably mounted by
means of a connector. The control package 10 includes a processor
11 for controlling the circuit packages 30, an parallel I/O
interface 12 for data communication with external systems, and
interfaces for data communication with the host
supervisory/controlling apparatus 20 and the packages 30 to be set.
The file package 40 includes a backup memory 41 for storing
start-up setting data, a battery 42 for supplying power to the
backup memory 41, and a mode setting switch 43 that indicates
whether there has occurred replacement work on the file package
40.
In the transmission apparatus having the above configuration, an
operation of replacing a faulty circuit package with a new one or
the same circuit package in another transmission apparatus is
performed manually. In such an operation, there occurs no problem
in replacing the control package 10 or the package 30 to be set.
However, since the file package 40 stores data to be set in the
associated transmission apparatus, a file package that has already
been used in another transmission apparatus cannot be used for
replacement as it is.
Therefore, a certain availability checking means is needed which
allows the processor 11 of the control package 10 to recognize
whether the start-up setting data stored in the file package 40 is
available. In the above conventional apparatus, the mode setting
switch 43 is provided as an availability checking means and a
switching operation therefor is performed manually. More
specifically, in restarting the apparatus, the processor 11 of the
control package 10 checks the state of the mode setting switch 43.
If the mode setting switch 43 is on, the processor 11 judges that
the file package 40 is a substituted one. Thus, the processor 11
initializes the backup memory 41, starts up the apparatus, and
stores start-up setting data of the respective packages into the
backup memory 41. Upon completion of the restart of the apparatus,
an operator switches the mode setting switch 43 to the off state.
On the other hand, if the mode setting switch 43 is off in
restarting the apparatus, the processor 11 judges that the file
package 40 is not a substituted one. Thus, the processor 11 reads
the start-up setting data from the backup memory 41, and restarts
the apparatus.
A description will be made of another general availability checking
means. First, in mounting the control package 10 and the file
package 40, a particular pattern that was determined when the
transmission apparatus was designed is stored into the backup
memory 41. When the apparatus is restored from a power shutoff
state, the processor 11 reads a pattern from the backup memory 41,
and judges availability of the data stored in the backup memory 41
based on whether the readout pattern is the preset particular
pattern.
However, in the conventional system in which the mode setting
switch 43 is operated manually, it cannot be checked whether the
start-up setting data stored in the backup memory 41 is available.
Further, an operator is required to be present until completion of
restarting. Since there are many packages to be set, it is very
difficult to improve the working efficiency. Further, it is
virtually impossible to be free of careless mistakes.
While the availability checking method using the particular pattern
can check whether the file package 40 is the same one, it cannot
check the start-up setting data of the backup memory 41 is
available. This is so because even if the file package 40 is the
same, a possibility is not denied that during power shutoff the
file package 40 was used in another transmission apparatus and the
data was written.
As described above, in the conventional system, it cannot be
checked whether the start-up setting data stored in the backup
memory was changed while the system was stopped. Therefore, for
instance, when the power is shut off for maintenance and
inspection, or the like, it is not completely assured that the same
start-up setting data is stored. In particular, if a transmission
apparatus in a switching system is restarted with start-up setting
data of another transmission apparatus, a wrong connection state is
established in the transmission apparatus concerned, causing too
large influences on society. Therefore, there exists a problem that
the apparatus cannot be restarted automatically when it is restored
from a power shutoff state, for instance.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a control system
which can positively judge whether data stored in a backup memory
is the same as the previous data, when the apparatus is
restarted.
Another object of the invention is to provide a method and system
which can automatically restart an apparatus having a backup
memory.
A further object of the invention is to provide a circuit package
including a backup memory in which, when the apparatus is
restarted, a control package can positively judge whether data
stored in the backup memory is the same as the previous data.
A backup memory package according to the present invention is
detachably connected to a control system by means of a connection
board. The control system is comprised a plurality of circuit
packages detachably connected to the connection board, each circuit
package requiring start-up setting data for start-up operation. The
backup memory package is comprised of a battery for supplying power
to the backup memory package through a power line and a backup
memory for storing the start-up setting data.
The backup memory package is further provided with a battery
monitor, a connection/disconnection member, and a flag memory. The
monitor checks a voltage of a monitor input terminal at all times
and generates a reset signal when the voltage of the monitor input
terminal becomes lower than a predetermined reference voltage. The
connection/disconnection member connects the monitor input terminal
to the power line when the backup memory package is connected to
the connection board, and disconnects the monitor input terminal
from the power line when the backup memory package is removed from
the connection board. The flag memory stores one of a set state and
a reset state, and changes in state from the set state to the reset
state when the reset signal is received from the monitor.
The control package controls the circuit packages and the backup
memory package through the connection board, and determines whether
the start-up setting data stored in the backup memory is valid or
not, by checking the flag state of the flag memory, set or
reset.
More specifically, the connection/disconnection member comprises a
first connector and a second connector. The first connector is
provided in the backup memory package, having a plurality of
conductors for electrically connecting the backup memory package to
the connection board. Two conductors thereof are connected to the
power line and the monitor input terminal, respectively. The second
connector is provided in the connection board detachably connected
to the first connector. The second connector has a plurality of
conductors corresponding to those of the first connector, two
conductors thereof corresponding to the two conductors of the first
connector are connected to each other, forming a return wire.
The monitor monitors a voltage of the battery through the power
line and the connection/disconnection member when the backup memory
package is connected to the connection board. The monitor outputs
the reset signal to the flag memory when the backup memory package
is removed from the connection board or when a voltage of the
battery becomes lower than the predetermined reference voltage. The
predetermined reference voltage is preferably set higher than a
minimum voltage that assures holding of data stored in the backup
memory and the flag memory.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram showing an example of a conventional
control system;
FIG. 2 is a block diagram showing a control system according to an
embodiment of the present invention;
FIG. 3 is a block diagram showing a more detailed configuration of
a file package in the embodiment;
FIG. 4 is a flowchart showing a start-up control flow performed in
the embodiment when the file package is mounted;
FIG. 5 is a flowchart showing a restart control flow performed in
the embodiment when the file package is available; and
FIG. 6 is a flowchart showing a restart control flow performed in
the embodiment when the file package is not available.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 2, a file package 101 is detachably connected to
a backboard 201 via a connector 202, and a control package 301 is
detachably connected to the backboard 201 via connectors 203 and
204. A plurality of circuit packages 401 to be set are detachably
connected to the backboard 201 via respective connectors 205, which
are connected to the connector 204 via the backboard 201. The
control package 301 is connected to a host supervisory/controlling
apparatus 501.
The file package 101 has a backup memory 102 which stores start-up
setting data that are necessary to start up the packages 401 to be
set. A data bus, an address bus, and a control bus of the backup
memory 102 are connected to the connector 202 via a bus buffer 103.
A backup battery 104 supplies power to the backup memory 102, a
power monitoring circuit 105 and a flip-flop circuit 106 via a
power line 107. The power line 107 is also connected to the
connector 202, and is returned to the file package 101 via a return
wire 206 (located in the backboard 201) and connected to a
monitoring terminal SV of the power monitoring circuit 105.
Therefore, if the file package 101 is pulled off from the backboard
201, the power line 107 and the power monitoring terminal SV of the
power monitoring circuit 105 are necessarily disconnected
electrically from each other.
The power monitoring circuit 105 always monitors a voltage Vcc of
the battery 104 via the power line 107 and the return wire 206. If
the power supply voltage Vcc becomes lower than a predetermined
voltage, the power monitoring circuit 105 supplies a reset signal
to the flip-flop circuit 106. This signal may be thought of as a
disconnection signal. Since the power monitoring circuit 105
monitors the power supply voltage Vcc via the power line 107 and
the return wire 206, the voltage applied to the monitoring terminal
SV quickly decreases from Vcc when the file package 101 is pulled
off from the backboard 201. Therefore, the power monitoring circuit
105 can detect not only voltage reduction of the battery 104 but
also pulling off of the file package 101 from the backboard 201.
Thus, monitor 105 and connector 202 may be thought of as
cooperating to form a disconnection detector.
The reset terminal (R) of the flip-flop circuit 106 is connected to
the power monitoring circuit 105, and its set terminal (S) and
output terminal (Q) are connected to the connector 202. A grounding
line 108 is connected to the connector 202 and grounded in the
backboard 201.
The control package 301 has a processor 302 for controlling the
packages 401 to be set. A data bus, an address bus, and a control
bus of the processor 302 are connected to the connector 203 via a
bus buffer 303. The bus buffer 303 of the control package 301 and
the bus buffer 103 of the file package 101 are connected to each
other via the backboard 201 and the connectors 202 and 203, whereby
the processor 302 and the backup memory 102 are connected to each
other via the buses.
A parallel input/output (PIO) circuit 304 is connected to the
processor 302 via the bus. A one-bit output terminal of the PIO
circuit 304 is connected to the set terminal (S) of the flip-flop
circuit 106 of the file package 101 via the connectors 202 and 203.
On the other hand, the output terminal (Q)of the flip-flop circuit
106 is connected to a one-bit input terminal of the PIO circuit 304
via the connectors 202 and 203. Therefore, the processor 302 can
set the flip-flop circuit 106 of the file package 101 through the
PIO circuit 304, and can also check its output state.
Through an interface circuit 305 of the apparatus, the processor
302 can transmit the start-up setting data to the packages 401 to
be set, and perform supervision and control of their setting
states. Further, the processor 302 communicates with a host
supervisory/controlling apparatus 501 through a communication
circuit 306.
As shown in a detailed manner in FIG. 3, the file package 101 has a
connector 202A for connection to the backboard 201, and the return
wire is not provided in the connector 202A. Therefore, in a state
that the file package 101 is removed from the backboard 201, the
power line 107 of the file package 101 and the monitoring terminal
SV of the power monitoring circuit 105 are disconnected from each
other. The bus buffer 103, which is comprised of uni-directional
address bus buffer BB.sub.A and control bus buffer BB.sub.C and a
bi-directional data bus buffer BB.sub.D, connects pins of the
connector 202A and input/output terminals of the backup memory
102.
The power monitoring circuit 105 is comprised of a voltage
comparator 109, a reference voltage generator 110, and a reset
controller 111. The voltage comparator 109 compares a voltage
V.sub.P that is applied to the monitoring terminal SV with a
reference voltage V.sub.ref. If the monitoring voltage V.sub.P
becomes lower than the reference voltage V.sub.ref, the comparator
109 supplies a low-level voltage to the reset controller 111. The
reference voltage V.sub.ref is set higher than a minimum voltage
that assures holding of data stored in the backup memory 102 and
the flip-flop circuit 106.
Upon receiving the low-level voltage from the comparator 109, the
reset controller 111 supplies a reset signal to the reset terminal
(R) of the flip-flop circuit 106, to reset it. As described above,
when the file package 101 is removed from the backboard 201 or the
voltage Vcc of the battery 104 decreases, the voltage comparator
109 supplies the low-level voltage to the reset controller 106.
Start-Up Operation
When the file package 101 and the packages 401 to be set are
mounted on the backboard 201, the processor 302 of the control
package 301 first execute a start-up process of the packages 401 to
be set.
As shown in FIG. 4, the processor 302 initializes the backup memory
102 of the file package 101 and performs a memory check (S601). If
abnormality is found in the memory check (No in S602), which means
a failure of the file package 101, the processor 302 announces
warning and turns on an abnormality lamp for the package 101
(S603). Recognizing the warning, an operator replaces the faulty
file package 101 with a new one.
If the backup memory 102 is normal (Yes in S602), the processor 302
selects one subject package, and detects its setting state (S604).
If start-up setting of the selected subject package has already
been completed (Yes in S605), the processor 302 reads start-up
setting data from the selected subject package and stores it into
the backup memory 102 (S606). If the selected subject package has
not been subjected to start-up setting (No in S605), the processor
302 sets the default start-up setting data in the selected subject
package and, at the same time, stores that start-up setting data
into the backup memory 102 (S607). Steps S604-S607 are repeated
until all the packages 401 have been subjected to start-up setting
(S608).
If all the packages have been subjected to start-up setting (Yes in
S608), the processor 302 sets the flip-flop circuit 106 through the
PIO circuit 304 (S609), to complete the start-up of the
transmission apparatus.
Restart Operation
When the transmission apparatus that has been subjected to the
start-up setting in the above manner is recovered from a power
shutoff state due to, for instance, maintenance and inspection, the
processor 302 restarts the apparatus according to the following
steps.
As shown in FIG. 5, when the power is restored, the processor 302
first checks the state of the output terminal Q of the flip-flop
circuit 106 of the file package 101 through the PIO 304 (S701). The
set state of the flip-flop circuit 106 (Yes in S701) indicates that
the file package 101 has never been pulled off from the backboard
201 nor the voltage of the battery 104 has decreased during the
power shutoff. Therefore, the processor 302 can reset the
transmission apparatus concerned using the start-up setting data
stored in the backup memory 102.
The processor 302 selects one subject package, and detects its
setting state (S702). If start-up setting of the selected subject
package has already been completed (Yes in S703), it is checked
whether all the packages 401 have been subjected to start-up
setting (S705). If the selected subject package has not been
subjected to start-up setting (No in S703), the processor 302 reads
start-up data for the package concerned from the backup memory 102
of the file package 101, and installs it in the package concerned
through the interface 305 (S704). Steps S702-S704 are repeated
until all the packages 401 are subjected to start-up setting
(S705). When all the packages 401 have been subjected to start-up
setting (Yes in S705), the processor 302 restarts the transmission
apparatus.
On the other hand, the reset state of the flip-flop circuit 106 (No
in S701) indicates that, during power shutoff, the file package 101
has been replaced, it has been pulled off from the backboard 201,
or the voltage of the battery 104 has decreased to a value smaller
than the minimum voltage necessary to hold data of the memory.
Therefore, the processor 302 cannot reset the transmission
apparatus concerned using the start-up setting data stored in the
backup memory 102.
In this case, as shown in FIG. 6, the processor 302 executes a
restart process by a start-up operation that is performed in
mounting the file package 101 as shown in FIG. 4. More
specifically, as shown in FIG. 6, the processor 302 initializes the
backup memory 102 of the file package 101 and performs a memory
check (S801). If abnormality is found in the memory check (No in
S802), which means a failure of the file package 101, the processor
302 announces warning and turns on an abnormality lamp for the
package 101 (S803). Recognizing the warning, an operator replaces
the faulty file package 101 with a new one.
If the backup memory 102 is normal (Yes in S802), the processor 302
selects one subject package, and detects its setting state (S804).
If start-up setting of the selected subject package has already
been completed (Yes in S805), the processor 302 reads start-up
setting data from the selected subject package and stores it into
the backup memory 102 (S806). If the selected subject package has
not been subjected to start-up setting (No in S805), the processor
302 sets the default start-up setting data in the selected subject
package and, at the same time, stores that start-up setting data
into the backup memory 102 (S807). Steps S604-S607 are repeated
until all the packages 401 have been subjected to start-up setting
(S808).
If all the packages have been subjected to start-up setting (Yes in
S808), the processor 302 sets the flip-flop circuit 106 through the
PIO circuit 304 (S809), to complete the start-up of the
transmission apparatus.
According to the present invention, by checking the state of the
flip-flop circuit of the file package, the control package can
judge whether the file package has been removed. At the occurrence
of file package replacement, the start-up data of the backup memory
of the file package is judged to be not available. The power
monitoring circuit of the file package always monitors the battery.
When the battery voltage decreases, the power monitoring circuit
resets the flip-flop circuit. Thus, at the occurrence of battery
voltage reduction, the start-up setting data of the backup memory
is judged to be not available.
Therefore, the control system according to the present invention
can positively judge availability of the data stored in the backup
memory of the file package that is connected to the control package
and, for example, can automatically execute in a positive manner
the operation of restarting the apparatus in restoring it from a
power shutoff state.
* * * * *